1. The Field of the Invention
The present invention relates to improved slot load motion picture projectors, and, more specifically, to the means which connect the projector control lever to the film gate.
2. Description of the Prior Art
Slot load motion picture projectors are a species of projector which have a slot formed in the projector structure for edge wise loading of the film into the projector mechanism. Examples of this type of projector are described in the following two patents assigned to the assignee of the present invention: U.S. Pat. No. 3,734,602 issued May 22, 1973, and U.S. Pat. No. 3,737,220; issued June 5, 1973. The disclosure of these two patents is incorporated herein by reference. The projectors described in these patents include a control lever moveable between a load position and an operate position. The control lever is coupled thru suitable mechanical means to the various film engaging elements of the projector. Such film engaging elements include a supply reel film sprocket with associated pressure rollers, a film gate, sound drum with associated pressure rollers, a take up reel feed sprocket with associated pressure rollers, and various other rollers and film guide surfaces. When the control lever is in the load position the film engaging elements are positioned away from or out of the film slot to permit obstruction free edge wise insertion of the film into the slot. When the control lever is moved to the operate position the film engaging elements are caused to engage the film in a predetermined sequence to complete the film loading. The predetermined sequential movement of the film engaging elements is necessary to form loops at various places in the film projector mechanism. Such loops include an upper film loop between the supply reel feed sprocket and the film gate and a lower film loop between the film gate and the sound drum. To form the upper film loop in the projector referred to above, the film gate is closed during the initial portion of the control lever movement from the load position to the operating position. Control lever movement after the initial portion is then used to cause the supply reel film sprocket pressure rollers to entrain the film on a surface portion of the supply reel feed sprocket and to cause a rotation of the feed sprocket to form a loop between the closed film gate and the supply reel feed sprocket.
A mechanism for closing the film gate during the initial control lever movement is described in the above referenced patents. While this mechanism performs adequately, it requires a plurality of complex, close tolerance parts fabricated from wear resistent material. This mechanism must be run in over a period of time and then adjusted within close operating limits to perform satisfactorily. In use, the mechanism can go out of adjustment and require readjustment by a trained projector technician.
The present invention provides mechanical means to couple the control lever to the film gate to cause the film gate to close during the initial portion of the control lever movement. The mechanism embodied by the present invention for use with slot load motion picture projectors is inexpensive to manufacture and assemble, and requires no adjustment.